1. Field of the Invention
The present invention relates to a rail joint arrangement and a method of forming a rail joint.
2. Description of Related Art
A rail system, which permits more than one train to travel on one stretch of track of rail, is generally divided into sections or blocks. The purpose of dividing railroad rails of a rail system into sections is to detect the presence of a train on a section of rail at any given time. Each rail section is electrically isolated from all other sections so that a high electrical resistance can be measured over the rail section when no train is present in that section. When a train enters a rail section, the train will short circuit adjacent railroad rails in which the electrical resistance in the rail section drops, thereby indicating the presence of a train.
Railroad rails are generally welded to each other or attached to each other by a rail joint. Referring to FIG. 1A, a typical rail joint 2 having a rail end 4 of a first rail R1 and another rail end 6 of a second rail R2 is shown. Rail joint 2 is shown having an electrical insulator 8 and is connected by rail joint bar 12 and rail joint bar 10. Rail joint 2 also shows a gap between E-E where the electrical insulator 8 is placed. With reference to FIG. 1B, a cross section of rail joint 2 is shown illustrating a uniform gap width between the rail end 4 and rail end 6.
There are other different uniform gap shapes. In FIG. 2A, an illustration is shown of another rail joint 16 having angled rail ends at 45°. Rail joint 16 has a rail end 18 of a first rail R1′ and a rail end 20 of a second rail R2′, with an electrical insulator 22 within the gap that is formed between rail end 18 and rail end 20. A cross-sectional view of rail joint 16 shows the rail joint having rail end 18 and rail end 20, with a gap between E′-E′ and an electrical insulator 22 within the gap. As shown in FIG. 2A, the width of the gap is still uniform throughout the angled gap. Some prior art arrangements utilize 45° chamfers or small radii along upper and lower rail end edges to prevent sharp edges. Typically, these chamfers and radiused surfaces have a depth and width in the ranges of 0.030″-0.090″.
Presently, ends of rails are connected together by rail joints. Typically, as shown in FIGS. 1A, 1B, 2A, and 2B, rail ends abut each other with flat surfaces that form a uniform gap between the rail ends. Over time, the tensile and flexural forces are higher at a center portion of the rail joints where the two railroad rails are joined. Eventually, the forces acting upon the rails deteriorate the insulator between the rails and they become non-insulated and rub up against each other and form short circuits in the rails. Therefore, it is an object of the present invention to overcome this problem.